The interest in the collection and conservation of coins and related objects has been historically considered a personal interest activity, with little formal standards or controls concerning the trading of coins. The recent rise in the value of coins compared to earlier levels has promoted the trading of coins to a higher degree of professional structure, most significantly by the advent of commercial third party coin grading services who have developed systems to apply a widely accepted quality grade (based on a numerical scale from 1 to 70 with 70 being the highest quality). After examining and determining the grade of a coin, the commercial services place the coin in a clear plastic holder in which a grade label with a reference barcode is affixed. The clear plastic holder is then ultrasonically welded around the coin, thus permanently linking the grade to the coin within the case. A barcode is linked to the database which can be searched to confirm that the referenced coin was graded by the commercial service, along with some additional transaction details such as the date, place, person grading the coin, etc.
The grading service charges a fee for the provided services and gives a warranty of grading accuracy as part of the transaction value. The result of this commercial service is to allow the plastic encapsulated coins to be more readily traded as their trade value is directly linked to the professional quality grade on the plastic holder.
However, the current commercial grading services lack repeatability and consistency. Further, contemporary services are unable to prevent “grader shopping” in which a coin owner may specifically hunt for the highest value for a given coin since there is currently not common database or rigorous objective means for identifying a specific coin.
To develop an automated coin grading system, a number of features are required or useful. One contemplated system provides capture of an optical signature from the coin, a unique set of optical properties that are repeatable in detection and specific to an individual coin. Such a system could also capture a digital image of the coin. One useful mechanism for such a system would be a mechanism to center the coin on a viewing platform.